JAK2 and myeloproliferative neoplasm: GOF mutations in JAKs (JAK1, JAK2, JAK3) and STATs (particularly STAT3 and STAT5B), as well as alterations in cytokine receptors (IL7R, CRLF2) and negative regulators (SOCS1, PTPN2), are recurrent in myeloproliferative neoplasms and certain lymphoid cancers.